A Thermal Cycling Route for Processing Nano-grains in AISI 316L Stainless Steel for Improved Tensile Deformation Behaviour

Tarun Nanda; B. Ravi Kumar; Vishal Singh

doi:10.14429/dsj.66.9948

Tarun Nanda Mechanical Engineering Department, Thapar University, Patiala
B. Ravi Kumar MST Division, National Metallurgical Laboratory, Jamshedpur, Jharkhand, India
Vishal Singh Mechanical Engineering Department, Indus International University, Una-174301, India

DOI: https://doi.org/10.14429/dsj.66.9948

Keywords: Thermal cycling, dislocation-density, recrystallisation, cold deformation, stainless steel, strained-induced-martensite

Abstract

The present work significantly improved the mechanical strength of AISI 316L stainless steel by producing nano-sized grains. Steel was subjected to cold rolling followed by repetitive thermal cycling to produce ultra-fine/ nano-sized grains. The optimum processing parameters including extent of cold deformation, annealing temperature for thermal cycling, soaking period during each thermal cycle, and number of thermal cycles were determined through a systematic step-by-step procedure. After conducting thermal cycling under optimum conditions, a significant amount of grain size reduction was achieved. The effect of nano-sized grains on tensile deformation behavior was analysed. High cold deformation resulted in increased amount of stored strain energy. The stored strain energy accelerated the re-crystallisation kinetics during the thermal cycling process. Every thermal cycle resulted in irregular dispersal of stored energy. This irregular dispersal of stored energy favoured recrystallisation rather than grain growth and led to refinement of grains, in the absence of strain induced martensite. Repetitive thermal cycling promoted grain refinement and resulted in very significant grain size reduction with resultant grain size in the range of 800–1200 nm as compared to initial size of 90–120 μm. The resultant microstructure improved tensile strength by
106.8 per cent, from 590 MPa to 1220 MPa.

Author Biographies

Tarun Nanda, Mechanical Engineering Department, Thapar University, Patiala

Dr Tarun Nanda is currently working as an Assistant Professor in Mechanical Engineering Department at Thapar University, Patiala, Punjab. His research areas include processing of advanced high strength steels, stainless steels, and polymer based nanocomposites.

B. Ravi Kumar, MST Division, National Metallurgical Laboratory, Jamshedpur, Jharkhand, India

Dr B. Ravi Kumar is currently working as a Principal Scientist in MST Division at CSIR-National Metallurgical Laboratory, Jamshedpur. His research interests include materials characterisation and testing, processing of ultra-fine/nano-grained materials for improved mechanical properties.

Vishal Singh, Mechanical Engineering Department, Indus International University, Una-174301, India

Mr Vishal Singh received his Master’s in Production Engineering from Thapar University, Patiala, 2015. Currently, he is working as an Assistant Professor in Mechanical Engineering department at Indus International University, Una, Himachal Pradesh. His areas of interests include steel processing, production technologies, and composite materials.

References

REFERENCES

Li,Y.; Hu, S.; Shen, J. & Hu, B. Dissimilar welding of H62 brass-316L stainless steel using continuous-wave Nd:YAG laser. Mater. Manuf. Process, 2014, 29(8), 916–921.

Eskandari, M.; Najafizadeh, A. & Kermanpur, A. Effect of strain-induced martensite on the formation of nanocrystalline 316L stainless steel after cold rolling and annealing. Mat. Sci. Eng. A, 2009, 519, 46–50.

Rao, G.A.; Sankaranarayana, M. & Balasubramaniam, S. Hot isostatic pressing technology for defence and space applications. Def. Sci. J., 2012, 62(1), 73–80.

Tathgir, S. & Bhattacharya, A. Activated-TIG welding of different steels: influence of various flux and shielding gas. Mater. Manuf. Process, 2016, 31(3), 335–342.

Kumar, K.V.S.; Gejendhiran, S. & Prasath, M. Comparative investigation of mechanical properties in GMAW/GTAW for various shielding gas compositions. Mater. Manuf. Process, 2014, 29(8), 996–1003.

Sugur, V.S. & Manwani, G.L. Problems in storage and handling of red fuming nitric acid. Def. Sci. J., 1983, 33(4), 331–337.

Karimzadeh, A. & Rouhaghdam, A.S. Effect of nickel pre-plated on microstructure and oxidation behavior of aluminized AISI 316 stainless steel. Mater. Manuf. Process, 2016, 31(1), 87–94.

Ganesh, K.C.; Vasudevan, M.; Balasubramanian, K.R.; Chandrasekhar, N. & Vasantharaja, P. Thermo-mechanical analysis of TIG welding of AISI 316LN stainless steel. Mater. Manuf. Process, 2014, 29(8), 903–909.

Mishnev, R.; Shakhova, I.; Belyakov, A. & Kaibyshev, R. Deformation microstructures, strengthening mechanisms, and electrical conductivity in a Cu–Cr–Zr alloy. Mat. Sci. Eng. A, 2015, 629, 29–40.

Rao, K.S. & N, Hossein. Brittle failure in heterogeneous crystalline rocks. Def. Sci. J., 2008, 58(2), 285–294.

Ucok, I.; Ando, T. & Grant, N.J. Property enhancement in type 316L stainless steel by spray forming. Mat. Sci. Eng. A, 1991, 133, 284–287.

Chen, S.; Shibata, A.; Gao, S. & Tsuji, N. Formation of fully annealed nanocrystalline austenite in Fe–Ni–C alloy. Mater. T. JIM., 2014, 55(1), 223– 226.

Salishchev, G.A.; Zaripova, R.G. & Zakirova, A.A. Structure and properties of stainless steels subjected to severe plastic deformation. Metal Sci. Heat Treat., 2006, 48 (1–2), 70–75.

Ye, K.L.; Luo, H.Y. & Ly, J.L. Producing nanostructured 304 stainless steel by rolling at cryogenic temperature. Mater. Manuf. Process, 2014, 29(6), 754–758.

Sun, S.L.; Huang, Q.X. & He, W.W. New optimum extrusion parameters of 9% Cr ferritic steel tubes. Mater. Manuf. Process, 2016, 31(6), 751–757.

Kumar, B.R.; Das, S.K.; Mahato, B. & Ghosh, R.N. Role of strain-induced martensite on microstructural evolution during annealing of metastable austenitic stainless steel. J. Mater. Sci., 2009, 45, 911–918.

Misra, R.D.K.; Nayak, S.; Mali, S.A.; Shah, J.S.; Somani, M.C. & Karjalainen, L.P. Microstructure and deformation behaviour of phase-reversion-induced nanograined/ultrafine-grained austenitic stainless steel. Metall. Mater. Trans. A, 2009, 40, 2498–2509.

Mythili, R.; Saroja, S. & Vijayalakshmi, M. Study of strain induced martensite formation in a Ti modified 316 stainless steel bellow by transmission electron microscopy. T. Indian I. Metals, 2009, 62(6), 573–579.

Kumar, B.R.; Das, S.K.; Sharma, S. & Sahu, J.K. Effect of thermal cycles on heavily cold deformed AISI 304L austenitic stainless steel. Mat. Sci. Eng. A, 2010, 527, 875–882.

Li, Y.; Bu, F.; Kan, W. & Pan, H. Deformation-induced martensitic transformation behavior in cold-rolled AISI304 stainless steels. Mater. Manuf. Process, 2013, 28(3), 256–259.

Kumar, B.R.; Mahato, B.; Sharma, S. & Sahu, J.K. Effect of cyclic thermal process on ultrafine grain formation in AISI 304L austenitic stainless steel. Metall. Mater. Trans. A, 2009, 40, 3226–3234.

Matlock, D.K. & Speer, J.G. Processing opportunities for new advanced high-strength sheet steels. Mater. Manuf. Process, 2010, 25(1–3), 7–13.

Kumar, B.R. & Gujral, A. Plastic deformation modes in mono- and bimodal-type ultrafine-grained austenitic stainless steel. Metall. Micro. Analysis, 2014, 3(5), 397–407.

Szpunar, J.A.; Narayanan, R. & Li, H. Computer model of recrystallization texture in aluminium alloys. Mater. Manuf. Process, 2007, 22(7–8), 928–933.

Chia, K.H.; Jung, K. & Conrad, H. Dislocation density model for the effect of grain size on the flow stress of a Ti–15.2 at % Mo alloy at 4.2–650K. Mat. Sci. Eng. A, 2005, 409, 32–38.

Raghavan, V. Materials science and engineering. PHI Learning Private Limited, India, 2004. 285 p.

Roucoules, C.; Pietrzyk, M. & Hodgson, P.D. Analysis of work hardening and recrystallization during the hot working of steel using a statistically based internal variable model. Mat. Sci. Eng. A, 2003, 339, 1–9.

Samuel, K.G. & Rodriguez, P. On power-law type relationships and the ludwigson explanation for the stress-strain behaviour of AISI 316 stainless steel. J.Mater. Sci., 2005, 40, 5727–5731.

Samuel, E.I. & Choudhary, B.K. Universal scaling of work hardening parameters in type 316L (N) stainless steel. Mat. Sci. Eng. A, 2010, 527, 7457–7460.

Nakashima, K.; Suzuki, M.; Futamura, Y.; Tsuchiyama, T. & Takaki, S. Limit of dislocation density and dislocation strengthening in iron. Mater. Sci. Forum, 2006, 503–504, 627–632.

Dischino, A.; Kenny, J.M.; Salvatori, I. & Abbruzzese, G. Modelling primary recrystallization and grain growth in a low nickel austenitic stainless steel. J. Mater. Sci., 2001, 36, 593– 601.

Kolmogorov, A.N. On the statistical theory of crystallization of metals (translated title). Izv. Akad. Nauk. SSSR, 1937, 1, 355–359.

Avrami, M. Kinetics of phase change I. General theory. J. Chem. Phys., 1939, 7(12), 1103–1109.

Johnson, W.A. & Mehl, R.F. Reaction kinetics in processes of nucleation and growth. AIMMPE, 1939, 135(8), 416–442.

Avrami, M. Kinetics of phase change II. Transformation-time relations for random distribution of nuclei. J. Chem. Phys., 1940, 8(2), 212–224.

Avrami, M. Kinetics of phase change III. Granulation, phase change, and microstructure. J. Chem. Phys., 1941, 9(2), 177–184.

Gao, M.; Reid, C.N.; Jahedi, M. & Li, Y. Estimating equilibration times and heating/cooling rates in heat treatment of workpieces with arbitrary geometry. J. Mater. Eng. Perform., 2000, 9(1), 62–71.